There has been proposed a radio-controlled wristwatch (hereinafter referred to as “satellite radio-controlled wristwatch”) configured to receive a radio wave (hereinafter referred to as “satellite radio wave”) from an artificial satellite used for a positioning system, such as a Global Positioning System (GPS) satellite, to thereby adjust time. Such adjustment is possible because positioning signals typified by a GPS signal contain accurate time information. An ultra-high frequency wave is used for such a satellite radio wave, and hence a larger amount of information is sent per hour as compared to a low frequency wave used for a standard radio wave, which has been used in the related art for time adjustment on the ground. As a result, the time required for reception of the time information is considered to be reduced as compared to the case where the standard radio wave is received.
In Patent Literature 1, there is disclosed a GPS-equipped wristwatch corresponding to the satellite radio-controlled wristwatch. As described in paragraph 0040 in the literature, the GPS-equipped wristwatch disclosed therein carries out reception processing when a button is pressed for several seconds, for example, three seconds or more. When the reception is in progress in a time measuring mode, the second hand moves to the position of symbol “Time”. When GPS satellite acquisition has failed, the secondhand moves to the position of symbol “N”.